[Towertalk] Service ent gnd vs shack gnd

My shack is a 40' x 56' metal structure on a slab. The shack is on the
opposite end from the service entrance. EMT runs throughout the building
and back to the service panel. The power feed is all buried (200 amp
variety). 8' ground rods are located to the entrance to each building on
the property and at the service pole with the meter.
In the shack, a strip of EMT runs behind the rigs and screwed to the wall.
Several sets of duplex plug-ins are behind the rigs. The service ground is
where the line runs into the building. The shack ground is right behind the
rigs.
My question: Should I bond the EMT behind the rig to the shack ground? I'm
concerned that I'll be feeding noise into the RF ground. I'm also concerned
that the service ground is about 65' away (85' if you follow the EMT around
the building).
After pondering all this for some time, I'm considering not attaching the
EMT to the RF ground and opt instead for a very small spark gap fixture
between the two.
Comments?
Ford-N0FP
ford@cmgate.com